Mind & Brain See Inside The Search for Intelligence IQ is easy to measure and reflects something real. But scientists hunting among our genes for the factors that shape intelligence are discovering they are more elusive than expected By Carl Zimmer This is only a preview. Get the rest of this article now! Select an option below: Buy Digital Issue Customer Sign In *You must have purchased this issue or have a qualifying subscription to access this content It has been identified that the institution you are trying to access this article from has institutional site license access to Scientific American on nature.com. Click here to access this article in its entirety through site license access.